Earphone connection detecting system and mobile device for supporting the system

ABSTRACT

A system for detecting the connection of an earphone system to a mobile device is provided. The earphone connection detecting system detects an electrical signal from a mechanical change according to the insertion of the earphone jack plug of the earphone system into the jack interface of the mobile device, via a switching device electrically isolated from the earphone system, thereby identifying the connection of the earphone system to the mobile device.

PRIORITY

This application claims the benefit under 35 U.S.C. §119(a) of a Korean patent application filed on Dec. 13, 2011 in the Korean Intellectual Property Office and assigned Serial No. 10-2011-0133617, the entire disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a system that can correctly detect the connection of an earphone to a mobile device, without generating noise. More particularly, the present invention relates to a mobile device with the earphone connection detecting system.

2. Description of the Related Art

Mobile devices have been widely used because they can be easily carried. For example, most people in the Republic of Korea are using mobile devices since the devices allow users to make a voice call while they are moving. Such mobile devices of the related art are equipped with various types of functions in addition to the function of communicating voice call information between a caller and a called party. For example, a mobile device of the related art has a file playback function, such as an MP3 player, and an image collecting function, such as a digital camera. The mobile devices can also support functions for playing a mobile game or an arcade game, etc.

The mobile devices are equipped with earphone systems that allow the users to hear the audio sound clearer or to prevent the audio sound from being exposed. Therefore, mobile device users can hear music or broadcasts via the earphone systems, irrespective of time and place. An earphone system of the related art detects the connection of earphones to a mobile device when the jack plug of the earphones is electrically connected to the jack interface of the mobile device. In general, users first fit earphones in their outer ears and then insert the earphone system to a mobile device that is turned on. However, during the connection of the earphone system to the mobile device, electrical noise is generated and this inconveniences users.

In addition, earphone connection detecting systems of the related art have used a ground contact of the earphone in order to check the electrical contact state. However, this configuration cannot detect, if earphones are in an electrical short state, whether the jack plug is inserted to a mobile device.

SUMMARY OF THE INVENTION

Aspects of the present invention are to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a system that can correctly detect the connection of an earphone to a mobile device, without generating noise.

Another aspect of the present invention is to provide a mobile device with the earphone connection detecting system.

In accordance with an aspect of the present invention, a mobile device that supports an earphone connection detecting system is provided. The mobile device includes a jack interface with a cavity to which an earphone jack plug of an earphone system is inserted, a switching device, placed in the cavity, for performing a switching operation by a physical force according to the insertion of the earphone jack plug into the cavity, a detection circuit, electrically connected to the switching device, for generating an electrical change according to the switching operation of the switching device, and a controller, connected to the detection circuit, for detecting the insertion of the earphone jack plug to the jack interface via the electrical change.

In accordance with another aspect of the present invention, an earphone connection detecting system is provided. The earphone connection detecting system includes an earphone system with an output control unit and a jack plug connected to the output control unit, wherein the output control unit outputs audio signals and the jack plug, and a mobile device with a jack interface to which the jack plug is inserted, wherein the jack interface detects an electrical change from a mechanical change according to the insertion of the earphone jack plug to the jack interface.

Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates a configuration of an earphone connection detecting system according to an exemplary embodiment of the present invention;

FIG. 2 illustrates a schematic block diagram of a mobile device according to an exemplary embodiment of the present invention;

FIG. 3 illustrates a schematic view showing the configuration of an earphone jack plug and a jack interface of the earphone connection detecting system according to an exemplary embodiment of the present invention, when the earphone jack plug is inserted into the jack interface;

FIG. 4 illustrates a cross-sectional view of a dome key and circuit components related to the key, according to an exemplary embodiment of the present invention; and

FIG. 5 illustrates a schematic view showing the configuration of an earphone jack plug and a jack interface of the earphone connection detecting system according to another exemplary embodiment of the present invention.

Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention is provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention is provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces.

Although the drawings represent embodiments of the invention, the drawings are not necessarily to scale and certain features may be exaggerated or omitted in order to better illustrate and explain the invention. It should be understood that the invention is not limited to the drawing scale.

FIG. 1 illustrates a configuration of an earphone connection detecting system according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the earphone connection detecting system 10 includes a mobile device 100 and an earphone system 200.

The earphone system 200 includes an earphone jack plug 201, inserted into a jack interface 130 of the mobile device 100, and an earphone output unit 202, connected to the earphone jack plug 201, for outputting audio signals. The earphone jack plug 201 may include three or four contacts according to types of earphone systems. For example, the earphone jack plug 201 may be configured to include a left contact for the left earphone, a right contact for the right earphone, and a ground contact. In addition to the three contacts, the earphone jack plug 201 may further include a microphone contact if the earphone system 200 is implemented with a microphone or headset. The earphone output unit 202 includes an earphone left head, connected to the earphone left contact, for outputting a left audio signal, and an earphone right head, connected to the earphone right contact, for outputting a right audio signal. The earphone output unit 202 outputs, if the audio signal is a stereo audio signal, the right and left audio signals via the right and left heads respectively. On the contrary, if the audio signal is a mono audio signal, the earphone output unit 202 outputs the same mono audio signal to the right and left heads.

When the earphone system 200 connects to the mobile device 100, the earphone jack plug 201 is fitted into the jack interface 130. During the process, the earphone jack plug 201 applies a force to a dome key installed to the mobile device 100. The dome key generates an electrical signal according to the magnitude of the received force that is used to detect whether the earphone system 200 is connected to the mobile device 100.

Since the jack interface 130 of the mobile device 100 is electrically isolated from the earphone jack plug 201 of the earphone system 200, the earphone connection detecting system 10 can prevent noise that may be generated by the electrical change during the connection there between. In particular, since the mobile device 100 includes a circuit that connects to the dome key, the mobile device 100 can process a mechanical change according to the connection of the earphone jack plug 201 to the mobile device 100 as an electrical change and thus correctly detect the insertion of the earphone jack plug 201 to the jack interface 130 of the mobile device 100, irrespective of the states of the earphone jack plug 201.

Although the exemplary embodiment is implemented in such a way that the dome key is installed in the jack interface 130 of the mobile device 100 in order to detect the connection of the earphone system 200 to the mobile device 100, it should be understood that the exemplary embodiment is not limited thereto. That is, it should be understood that the dome key is an example of a variety of switching devices that are installed in the jack interface 130 of the mobile device 100, are configured such that their out sides are electrically isolated from the other components, and can convert a mechanical change to an electrical signal when the earphone jack plug 201 is inserted to the jack interface 130, so that the earphone connection detecting system 10 can detect the connection without causing electrical short when the earphone system 200 is connected to the mobile device 100. In the following description, an exemplary embodiment will be described, employing a dome key as an example of the isolated switching devices.

FIG. 2 illustrates a schematic block diagram of a mobile device according to an exemplary embodiment of the present invention.

Referring to FIG. 2, the mobile device 100 includes a communication unit 110, an input unit 120, a jack or earphone interface 130, a display unit 140, a storage unit 150, and a controller 160.

When the earphone jack plug 201 of the earphone system 200 is inserted into the jack or earphone interface 130 of the mobile device 100, applying a force to the dome key installed to the jack interface 130, the mobile device 100 can detect the mechanical change, according to the insertion of the earphone jack plug 201, as an electrical change. To this end, the mobile device 100 includes a circuit for detecting an electrical change corresponding to a mechanical change according to the insertion of the earphone jack plug 201 to the jack interface 130. The circuit is installed to one side of the dome key. When the circuit detects an electrical change, the mobile device 100 identifies the insertion of the earphone jack plug 201 to the jack interface 130. After that, the mobile device 100 may process signals to control the earphone system 200. As such, since the mobile device 100 can detect, via the circuit, an electrical change according to the insertion of the earphone jack plug 201 to the jack interface 130, the mobile device 100 can identify the connection of the earphone system 200 thereto, irrespective of the electrical characteristics of the earphone system 200. Alternatively, the mobile device 100 can detect the insertion of the earphone jack plug 201 to the jack interface 130, by using the change in the level of physical pressure according to the insertion of the earphone jack plug 201 into the jack interface 130, and this can prevent noise from being generated.

The communication unit 110 performs communication in the mobile device 100. If the mobile device 100 doesn't support a communication function, it may not include the communication unit 110. The communication unit 110 may be implemented with a module for providing a mobile communication function to the mobile device 100. The communication unit 110 establishes communication channels with mobile communication systems and transmits/receives signals thereto/therefrom. For example, the communication unit 110 establishes at least one of the channels for voice, video and data with other mobile communication systems, and transmits/receives signals via the channel.

The communication unit 110 may establish a communication channel with an external server or other mobile device, and receive audio signals therefrom. The mobile device 100 may transmit the audio signals, received via the communication unit 110, to the earphone system 200 according to the settings. For example, if the mobile device 100 is connected to a music service server via a communication channel of the communication unit 110, the mobile device 100 may receive audio signals and transmit them to the earphone system 200 via the jack interface 130 according to the control of the controller 160.

The input unit 120 generates signals required for the operation of the mobile device 100. The input unit 120 may be implemented with a keyboard, a keypad, key buttons, etc. according to the compatibility of the mobile device 100. If the display unit 140 is implemented with a touch screen, the input unit 120 may be a touch map displayed thereon. The input unit 120 generates a signal for controlling the path of outputting audio signals, according to the insertion of the earphone jack plug 201 to the jack interface 130 of the mobile device 100. For example, if the earphone jack plug 201 of the earphone system 200 is inserted to the jack interface 130 of the mobile device 100, the input unit 120 may generate, according to the user's selection, a signal for selecting one of the modes where the audio signal is output via the earphone system 200 (i.e., earphone output mode) and via the loudspeakers (i.e., speaker output mode). The earphone output mode may be enabled when the earphone jack plug 201 is inserted into the jack interface 130, and disabled if the earphone jack plug 201 is not inserted thereto.

The jack interface 130 receives the earphone jack plug 201 of the earphone system 200. The jack interface 130 refers to a connector for affixing the inserted earphone jack plug 201. The jack interface 130 includes a number of contacts that contact corresponding contacts of the earphone jack plug 201. The jack interface 130 further includes a dome key that can detect the mechanical change, created during the insertion of the earphone jack plug 201 into the jack interface 130, as an electrical change. A detailed description of the jack interface 130 will be provided later referring to the accompanying drawings.

The display unit 140 provides screen interfaces required for the operation of the mobile device 100, for example, an idle screen, menu screens, etc. In particular, the display unit 140 supports a variety of screen interfaces related to the operation of the earphone system 200. For example, if the earphone jack plug 201 of the earphone system 200 is inserted into the jack interface 130, the display unit 140 may display a text message or an image informing the user of the insertion of the earphone jack plug 201 into the jack interface 130 on the screen. Alternatively, the display unit 140 may display the text message or image on the screen while the earphone jack plug 201 is being inserted into the jack interface 130 or may display temporarily the text message or image on the screen when the earphone jack plug 201 is inserted into the jack interface 130. In addition, when the earphone jack plug 201 is removed from the jack interface 130, the display unit 140 may display a text message or image informing the user of the removal of the earphone jack plug 201 on the screen for a certain period of time.

The display unit 140 displays a control map for controlling the audio signal output path of the earphone system 200. The control map includes a key map for selecting one of the output paths of audio signals from the mobile device 100 to the speaker and from the mobile device 100 or to the earphone system 200 via the jack interface 130 and the earphone jack plug 201. To this end, the display unit 140 may be implemented with a touch screen with a display panel and a touch panel. In that case, the display panel may display the image corresponding to the control map, etc. The touch panel sets a touch effective area and a non-touch effective area in order to control the control map displayed on the display panel, and transfers a signal corresponding to a touch event that occurs on the touch effective area to the controller 160.

The speaker outputs audio signals generated when the mobile device 100 plays back audio files and is operated. If the mobile device 100 supports a communication function and a function for transmitting the user's voice, the mobile device 100 may further include a microphone. In particular, if the mobile device 100 connects to the earphone system 200, the speaker may not output audio signals. When the earphone jack plug 201 of the earphone system 200 is removed from the jack interface 130 of the mobile device 100, the speaker may output the audio signals under the control of the controller 160.

The storage unit 150 stores an operating system of the mobile device 100, and application programs for executing functions and related algorithms, according to the exemplary embodiments. The storage unit 150 also stores audio files corresponding to audio data that will be output to the speaker and the earphone system 200. When the audio files are played back according to the user's request, the audio signals are output to the speaker or the earphone system 200 if the earphone system 200 is connected to the mobile device 100.

The controller 160 controls the signals flowing among the components in the mobile device 100. The controller 160 controls the transmission, process, deletion, and correction with respect to information.

The controller 160 may include a port for detecting the connection of the earphone system 200 to the mobile device 100, via the dome key that coverts a mechanical change to an electrical change according to the insertion of the earphone jack plug 201 into the jack interface 130. The detection port includes a signal line connected to the circuit connected to the dome key. The controller 160 can detect, via the detection port, a signal corresponding to the electrical change generated when the dome key is pressed according to the insertion of the earphone jack plug 201 to the jack interface 130. In that case, the controller 160 outputs signals to the earphone system 200. That is, if the controller 160 identifies the insertion of the earphone jack plug 201 into the jack interface 130, the controller 160 outputs audio signals to the earphone system 200, via the ports connected to the right and left contacts of the earphone jack plug 201 respectively. To this end, the controller 160 includes a coder and decoder (CODEC) 161. The CODEC 161 includes a detection port, and right and left ports. The jack interface 130 of the mobile device 100 and the earphone jack plug 201 of the earphone system 200 will be described in detail as follows, referring to the accompanying drawings.

FIG. 3 illustrates a schematic view showing the configuration of an earphone jack plug and a jack interface of the earphone connection detecting system according to an exemplary embodiment of the present invention, when the earphone jack plug is inserted into the jack interface.

Referring to FIG. 3, the earphone jack plug 201 has left L and right R audio signal plug contacts, a ground plug contact E_GND, and a microphone plug contact E_MIC, in sequential order, from the tip of the earphone jack plug 201. The contacts of the jack plug 201 are electrically isolated from each other via isolation members or rings. In an exemplary embodiment, although the earphone jack plug 201 inserted into the jack interface 130 includes four contacts, it should be understood that the exemplary embodiment is not limited thereto. For example, the earphone jack plug 201 may be modified in such a way to include three contacts, left L and right R audio signal plug contacts, and a ground plug contact E_GND, without the microphone plug contact E_MIC. Alternatively, the earphone jack plug 201 may also be modified in such a way that the position of the ground plug contact E_GND of the four contacts is exchanged with that of the other plug contact. That is, the earphone jack plug 201 inserted into the jack interface 130 of the mobile device 100, according to this other exemplary embodiment, can be applied to conventional earphone systems. In the following description, the exemplary embodiment will be described based on the earphone jack plug 201 with four plug contacts as shown in FIG. 3.

The jack interface 130 of the mobile device 100 is designed to have a cavity 131 that is long to receive the earphone jack plug 201. The cavity 131 forms jack contacts on the inner wall at locations in such a way as to contact the contacts of the jack plug 201. That is, the cavity 131 includes a left audio signal jack contact EAR_L that contacts the left audio signal plug contact L, a right audio signal jack contact EAR_R that contacts the right audio signal plug contact R, a ground jack contact EAR_GND that contacts the ground plug contact E_GND, and a microphone jack contact EAR_MIC that contacts the microphone plug contact E_MIC. In particular, the jack interface 130 is designed in such a way that the dome key 133 is formed at the end or on the deepest bottom of the jack interface 130 and the detection circuit 135 is placed near the dome key 133, so that the dome key 133 is mechanically pressed by the tip of the earphone jack plug 201 and the detection circuit 135 converts the mechanical change of the dome key 133 to an electrical signal and transfers the electrical signal to the controller 160.

When the earphone jack plug 201 of the earphone system 200 is inserted into the jack interface 130 of the mobile device 100, the tip of the jack plug 201 presses the dome key 133 of the cavity 131, thereby generating a mechanical deformation to a switching circuit in the dome key 133. In that case, the detection circuit 135 connected to the switching circuit converts the mechanical change of the dome key 133 to the electrical change and transfers the corresponding signal to the controller 160.

The jack interface 130 is designed in such a way that the earphone jack plug 201 is fitted into the cavity 131 so that the earphone jack plug 201 cannot be easily removed therefrom. For example, if the cavity 131 of the interface 130 has the inner diameter of 3.5 mm, the jack plug 201 has also the same size in the external diameter. The jack interface 130 may also be designed in such a way that the internal wall of the cavity 131 is made of an elastic material to hold the earphone jack plug 201 inserted therein. In that case, the jack contacts of the interface 130 may protrude from the inner wall of the cavity 131 so that the contacts can correctly contact the plug contacts of the earphone jack plug 201.

In particular, the jack interface 130 is designed in such a way that the cavity 131 has a depth so that the dome key 133 placed on the bottom or at the deepest location of the jack interface 130 can be pressed by the jack plug 201 when the earphone jack plug 201 is completely fitted into the cavity 131, and physically deformed by the mechanical pressure. For example, the cavity 131 may be formed to have a depth in such a way that the depth between the top of the dome key 133, when the dome key 133 doesn't receive an external force, and the opening of the cavity 131 is less than the length of the entire contact of the jack plug 201, and the depth between the top of the dome key 133, when the dome key 133 receives an external force by the jack plug 201, and the opening of the cavity 131 is similar to the length of the entire contact of the jack plug 201.

FIG. 4 illustrates a cross-sectional view of a dome key and circuit components related to the key, according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the dome key 133 includes a first switch electrode 31, a second switch electrode 33, an isolation layer 35, and an adhesive layer 37. The adhesive layer 37 may be implemented with a variety of fixing members if they can fix the dome key 133 to the bottom of the jack interface 130, for example, the fixing members may be screws. If the dome key 133 is designed in such a way that both sides of the dome key 133 are equipped with hooks, the adhesive layer 37 may include members to be coupled with the hooks. The adhesive layer 37 may fix the dome key 133 to the bottom of the jack interface 130.

The detection circuit 135 is configured in such a way that a pull-up resistor R is connected to a node on a wire connecting the first switch electrode 31 and the detection port DET of the CODEC 161, a reference voltage source VDD outputs a certain level of voltage via the pull-up resistor R, and the ground electrode GND connects to the second switch electrode 33.

The dome key 133 is configured in such a way that the first switch electrode 31 and the second switch electrode 33 are spaced apart from each other by a certain distance. However, the exemplary embodiment is not limited thereto and other types of switching mechanisms may be used. The dome key 133 is placed in the isolation layer 35. If the isolation layer 35 experiences an external force, the first switch electrode 31 contacts the second switch electrode 33. In that case, since the first 31 and second 33 electrodes are grounded to the ground electrode GND, the node connecting the pull-up resistor R and the detection port DET goes to ground. Therefore, the CODEC 161 receives a signal corresponding to the electrical change via the detection port DET. That is, the CODEC 161 detects the change in the input voltage level of the detection port DET from the voltage level of VDD to the ground level. As such, the CODEC 161 can identify the insertion of the earphone jack plug 201 into the jack interface 130 by detecting the input voltage level at the detection port DET.

Meanwhile, since the first 31 and second 33 switch electrodes of the dome key 133 are covered with the isolation layer 35 and electrically isolated from the outside, the first 31 and second 33 switch electrodes don't contact the earphone jack plug 201 when the plug 201 applies a physical force to the dome key 133. Therefore, when the dome key 133 experiences a physical force, the detection circuit 135 generates an electrical change corresponding to the physical force, and the CODEC 161 thus identifies the insertion of the earphone jack plug 201 to the jack interface 130 irrespective of the electrical state of the earphone system 200. If the earphone jack plug 201 is inserted into the jack interface 130, the CODEC 161 enables the left audio signal port L_Port, the right audio signal port R_Port, and a microphone signal port MIC_Port to transmit/receive signals to/from the left audio signal jack contact EAR_L, the right audio signal jack contact EAR_R, and the microphone jack contact EAR_MIC of the jack interface 130, via signal lines.

FIG. 5 illustrates a schematic view showing the configuration of an earphone jack plug and a jack interface of the earphone connection detecting system according to another exemplary embodiment of the present invention.

Referring to FIG. 5, the jack interface 130 of the mobile device 100 forms a dome key 133 on the inner wall. The earphone jack plug 201 includes four contacts, i.e., left L and right R audio signal plug contacts, a ground plug contact E_GND, and a microphone plug contact E_MIC, in that sequential order, from the tip. However, it is noted that this order of the contacts is merely an example and the contacts may be arranged in a different order.

The jack interface 130 includes a cavity 131, a dome key 133 formed on the inner wall of the cavity 131, and a number of contacts on the inner wall of the cavity 131. The cavity 131 is long so as to receive the earphone jack plug 201. The contacts are a left audio signal jack contact EAR_L that contacts the left audio signal plug contact L, a right audio signal jack contact EAR_R that contacts the right audio signal plug contact R, a ground jack contact EAR_GND that contacts the ground plug contact E_GND, and a microphone jack contact EAR_MIC that contacts the microphone plug contact E_MIC. In particular, the cavity 131 of the interface 130 has an inner diameter similar to the external diameter of the earphone jack plug 201, for example, 3.5 mm. The inner wall of the cavity 131 may be made of a material with elasticity and high frictional coefficient, non-conductivity, e.g., rubber, synthetic rubber, polyurethane, etc., so that the earphone jack plug 201 fitted into the cavity 131 cannot be easily removed therefrom.

Referring to FIG. 5, the jack interface 130 may include at least one dome key 133 on the inner wall of the cavity 131. The dome key 133 contacts the side of the earphone jack plug 201 and experiences a physical force according to the insertion of the plug 201 into the cavity of the jack interface 130. In that case, the dome key 133 converts the physical force to an electrical change or signal and transfers the signal to the CODEC 161.

Referring to FIG. 4, since the first 31 and second 33 switch electrodes of the dome key 133 are covered with the isolation layer 35 and electrically isolated from the outside, the first 31 and second 33 switch electrodes don't contact the earphone jack plug 201 when the plug 201 applies a physical force to the dome key 133. That is, the dome key 133 can convert the physical force to an electrical signal without electrically contacting the earphone jack plug 201.

Although this exemplary embodiment is implemented in such a way that the dome key 133 is formed on the inner wall at a place corresponding to a position of the right audio signal plug contact R of the earphone jack plug 201, it should be understood that the exemplary embodiment is not limited thereto. For example, the dome key 133 may be formed on the inner wall at a place corresponding to a position of any one of the remaining contacts of the earphone jack plug 201, i.e., the left audio signal plug contact L, the ground plug contact E_GND, and the microphone plug contact E_MIC. Meanwhile, the exemplary embodiment may be modified in such a way that the jack interface 130 may form a number of dome keys on the inner wall. This configuration is advantageous in that, if one of a number of dome keys is broken down, the remaining dome keys can convert the physical force to an electrical change and transfer the corresponding signal to the detection circuit, so that the connection detection system can identify the insertion of the earphone jack plug 201 to the jack interface 130.

As described above, the earphone connection detecting system and the mobile device with the system, according to the exemplary embodiments, can correctly detect the connection of an earphone to the mobile device, without generating noise.

Although it is not shown in the drawings, the mobile device may selectively further include various types of components, for example: a short-range communication module for short-range communication; a camera module for acquiring still images/videos; an interface for transmitting/receiving data in a wireless or wired mode; an Internet communication module; and a digital broadcast module for receiving and reproducing broadcasts. With the spread of digital convergence, although it is impossible to list all the modifications of mobile devices in this description, it will be easily appreciated to those skilled in the art that the other components equivalent to the above-listed components may be further included in the mobile device according to the invention. Also, it will be appreciated that, according to the purposes, the mobile device may be implemented by omitting a particular component or replacing it with other components.

The mobile device according to the described exemplary embodiments includes all information communication devices, multimedia devices, and their applications, which include an earphone interface that various types of jacks for earphones are plugged into and are operated according to communication protocols corresponding to various types of communication systems. For example, the mobile device can be used in mobile communication terminals, Portable Multimedia Players (PMPs), digital broadcast players, Personal Digital Assistants (PDAs), audio players (e.g., MP3 players), mobile game players, smartphones, laptop computers, hand-held PC, etc.

While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. 

What is claimed is:
 1. An earphone connection detecting system comprising: an earphone system comprising an output control unit and an earphone jack plug connected to the output control unit, wherein the output control unit outputs audio signals to the earphone jack plug; and a mobile device with a jack interface to which the earphone jack plug is inserted, wherein the jack interface detects an electrical change from a mechanical change according to the insertion of the earphone jack plug into the jack interface.
 2. The earphone connection detecting system of claim 1, wherein: the jack interface comprises a cavity to which the earphone jack plug is inserted; and the mobile device comprises: a switching device, disposed in the cavity, for performing a switching operation by a physical force according to the insertion of the earphone jack plug into the cavity; a detection circuit, electrically connected to the switching device, for generating an electrical change according to the switching operation of the switching device; and a controller, connected to the detection circuit, for detecting a connection of the earphone system to the mobile device via the electrical change.
 3. The earphone connection detecting system of claim 2, wherein the switching device comprises: an isolation layer of a preset thickness; and first and second switch electrodes spaced apart from each other by a certain distance, disposed on the isolation layer.
 4. The earphone connection detecting system of claim 3, further comprising: a member for fixing the switching device into the cavity of the jack interface.
 5. The earphone connection detecting system of claim 3, wherein the detection circuit comprises: a pull-up resistor connected to the first switch electrode; a reference voltage source connected to the pull-up resistor; a ground electrode connected to the second switch electrode; and a signal line connecting the pull-up resistor and the controller.
 6. The earphone connection detecting system of claim 2, wherein the switching device is disposed on a bottom of the cavity of the jack interface and contacts a tip of the earphone jack plug.
 7. The earphone connection detecting system of claim 2, wherein the switching device is disposed on an inner wall of the jack interface at one or more places corresponding to positions of contacts of the earphone jack plug.
 8. A mobile device that supports an earphone connection detecting system, the mobile device comprising: a jack interface comprising a cavity to which an earphone jack plug of an earphone system is inserted; a switching device, disposed in the cavity, for performing a switching operation by a physical force according to the insertion of the earphone jack plug into the cavity; a detection circuit, electrically connected to the switching device, for generating an electrical signal according to the switching operation of the switching device; and a controller, connected to the detection circuit, for detecting the insertion of the earphone jack plug into the jack interface via the electrical signal.
 9. The mobile device of claim 8, wherein the switching device comprises: an isolation layer of a preset thickness; and first and second switch electrodes spaced apart from each other by a certain distance, disposed in the isolation layer.
 10. The mobile device of claim 9, further comprising: a member for fixing the switching device into the cavity of the jack interface.
 11. The mobile device of claim 9, wherein the detection circuit comprises: a pull-up resistor connected to the first switch electrode; a reference voltage source connected to the pull-up resistor; a ground electrode connected to the second switch electrode; and a signal line connecting the pull-up resistor and the controller.
 12. The mobile device of claim 9, wherein the switching device is disposed on a bottom of the cavity of the jack interface and contacts a tip of the earphone jack plug.
 13. The mobile device of claim 9, wherein the switching device is disposed on an inner wall of the jack interface at one or more places corresponding to positions of contacts of the earphone jack plug.
 14. A jack interface system comprising: a cavity in which an earphone jack plug of an earphone system is inserted; a switching device, disposed in the cavity, for performing a switching operation according to a physical force exerted by the earphone jack plug on the switching device when inserting the earphone jack plug into the cavity; a detection circuit, electrically connected to the switching device, for generating an electrical signal according to the switching operation of the switching device; and a controller, connected to the detection circuit, for detecting the insertion of the earphone jack plug into the jack interface via the electrical signal.
 15. The jack interface system of claim 14, wherein the switching device comprises: an isolation layer of a preset thickness; and first and second switch electrodes spaced apart from each other by a certain distance, disposed in the isolation layer.
 16. The jack interface system of claim 15, further comprising: a member for fixing the switching device into the cavity of the jack interface.
 17. The jack interface system of claim 15, wherein the detection circuit comprises: a pull-up resistor connected to the first switch electrode; a reference voltage source connected to the pull-up resistor; a ground electrode connected to the second switch electrode; and a signal line connecting the pull-up resistor and the controller.
 18. The jack interface system of claim 15, wherein the switching device is disposed on a bottom of the cavity of the jack interface and contacts a tip of the earphone jack plug.
 19. The jack interface system of claim 15, wherein the switching device is disposed on an inner wall of the jack interface at one or more places corresponding to positions of contacts of the earphone jack plug. 